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Greenhouse Gas Emissions from Ground Level Area Sources in Dairy and Cattle Feedyard Operations

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  • University of Florida (UF)

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A protocol that consisted of an isolation flux chamber and a portable gas Chromatograph was used to directly quantify greenhouse gas (GHG) emissions at a dairy and a feedyard operation in the Texas Panhandle. Field sampling campaigns were performed 5 days in a week during daylight hours from 9:00 to 7:00 pm each day. The objective of this research was to quantify and compare GHG emission rates (ERs) from ground level area sources (GLAS) at dairy and cattle feedyard operations during the summer. A total of 74 air samples using flux chamber were collected from the barn (manure lane and bedding area), loafing pen, open lot, settling basin, lagoons, and compost pile within the dairy operation. For the cattle feedyard, a total of 87 air samples were collected from four corner pens of a large feedlot, runoff holding pond, and compost pile. Three primary GHGs (methane, carbon dioxide, and nitrous oxide) were measured and quantified from both operations. The aggregate estimated ERs for CH4, CO2, and N2O were 836, 5,573, 3.4 g hd-1d-1 (collectively 27.5 kg carbon dioxide equivalent (CO2e) hd -1 d-1), respectively, at the dairy operation. The aggregate ERs for CH4, CO2, and N2O were 3.8, 1,399, 0.68 g hd-1 d-1 (1.7 kg CO2e hd -1 d-1), respectively, from the feedyard. Aggregate CH4′ CO2′ and N2O ERs at the dairy facility were about 219, 4 and 5 times higher, respectively, than those at the feedyard.
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